I'm glad to know that #2 is a friend because it's popping up everywhere. #4 IS a gas plant---I was thinking that's what it might be. Amber (S's sister) planted that when she visited last spring, but it didn't do anything. This year might be different, it appears. Number 3 I think is foe, but I still don't know. Number 1 I'm still not sure about... Any other opinions?

Not sure. I thought #2 was nicotiana of some sort, but I'll go with rudbeckia too. :) I'd pull #1. Heck, I pull most things because volunteers tend to get thuggish in my garden ('specially chamomile and borage). I also thought #3 was cranesbill... mine is flowering now in part shade so if yours is the same it should start soon.MAC